Oil or gas pollution control apparatus and method

ABSTRACT

A method which is particularly suitable to prevent oil pollution of water in the vicinity of an offshore drilling operation. Apparatus is provided for use on a ruptured oil and/or natural gas pipe where fluid is issuing under pressure from the pipe. A heat dissipating screen is disposed in the path of the fluid and raised to a predetermined position. The fluid is then intentionally ignited (thus preventing pollution), the heat dissipating effect of the screen confining the flame to a region above the screen, spaced from the open end of the well pipe. A thermal radiation shield can be provided as well as water coolant members for the screen and shield.

United States Patent Joseph D; Mode 7311 Vista Del Mar, Phys Del Rey, Calif. 90291 [Zl] Appl. No. 36,573

[22] Filed May 12,1970

[45] Patented A1331, 1971 72] Inventor [54] OIL OR POLLUTION CONTROL APPARATUS ANDME'I'IIOD zocm snnwin m 52] us. cl 166/.5, 431/2, 431/328, 165/47 51 16cm A62c3/00,

1 E2lb7/l2,E2lb35/00 1501 Field oISearch 166 .s,;6, 302, 57,75; 169/2; 210/63; 165/47, 134;:131/2, 328,329

[56] ReiereuoesCited UNITED STATES PATENTS 1,859,606 5/1932 Sievem m1. 169/2X 1,857,788 5/1932 Murphy I 169/2 2,368,802 2/1945 Cartter et 431/329 X 2,935,841 5/1960 Myers et a1. 165/134 X 3,343,586 9/1967 Berchtold et a1. 431/329 X 3,503,443 3/1970 Blanding et al. 166/.6

Primary ExaminerStephen J. Novosad Au0rneyNi lsson, Robbins, Wills & Berliner ABSTRAC'Ii A method which is particularly suitable to prevent oil pollution of water in the vicinity of an offshore drilling operation. Apparatus is provided for use on a ruptured oil and/or natural gas pipe where fluid is issuing under pressure from the pipe. A heat dissipating screen is disposed in the ,path of the fluid and raised to a predetennined position. The

fluid is'then intentionally ignited (thus preventing pollution), the heat dissipating effect of the screen confining the flame to a region above the screen, spaced from the open end of the well pipe. A thermal radiation shield can be provided as well as water coolant members for the screen and shield.

ATENTEMUMI 19x 3 503 299 sum 1 OF 2 INVE NTOR.

JOS'PH D. MOZ/C BY wwmwmuw & Mm,

ATENTEU AUB3I I97 SHEET 2 BF 2 42 as 78/66 /02 M f? INVENTOR.

JOS'P/J 0. 4402/6 OIL OR GAS POLLUTION CONTROL APPARATUS AND METHOD BACKGROUND OF THE INVENTION 1. Field of the Invention The fields of art to which the invention pertains include the fields of oil and gas wells, the control and extinguishment of oil and gas well fires, and oil pollution.

2. Description of the Prior Art In the drilling of oil or gas wells, inadvertent, accidental blows" will occasionally occur in which the pipe casing ruptures causing fluid to discharge under pressure to the atmosphere. This geyserlike discharge is highly flammable and often ignites sending a large, high temperature flame hundreds of feet into the air. The intense radiant heat emitted by the flame prevents workmen from approaching the ruptured pipe. Accordingly, the flame is usually extinguished by detonating a high explosive as near as possible to the rupture area. A shock normal to eachother to define openings .through which the fluid can pass. Additionally, a thermal radiation shield can be disposed perimetrically about the screen and can be formed with coolant conducting tubes. An inlet manifold can connect the coolant tubes and water or other coolant can be pumped into the manifold and through the coolant tubes. With an offshore well, water can be drawn for this purpose from the in the path of the spewing fluid sothat escaping gas and/or oil exceeds the flame propagation rate, thus extinguishing the flame. With the flame extinguished, the workmen can enter the area to cap or seal the ruptured pipe. This generally involves clamping or affixing to the ruptured pipe some type of valved auxiliary piping which can then be closed to shutoff the flow of oil or gas.

With oil'wells, an additional stage of repair involves the collection and disposal of oil which has been spewed from the rupture and which has fallen to the ground following extinguishment of the flame but prior to capping of the ruptured pipe. The well can continue to spew oil for days or weeks depending upon the nature of the rupture and the difficulty of capping the ruptured pipe. Collection of the oil can consist of building earthen dams around the rupture site to localize the spilled oil which can then be pumped into tankers for removal. However, when the rupture occurs with an offshore oil well, oil retrieval is extremely difficult and presents a major and often tragic hazard. The economic losses of any blow" is high due to the inherent danger and the unique skills involved in extinguishing the fire and capping the well. With offshore passes through the screen and continues on into the atmosphere. Once positioned, a water pump may be actuated to drive water through the coolant tubes. The fluid above the screen is then intentionally reignited by means of an auxiliary flame or spark device, causing the fluid to burn with a flame front resting" on or slightly above the screen. Fluid below the screen remains unignited, permitting workmen to approach the ruptured area to begin the capping or sealing process.

Once the capping or sealing process is completed, the screen s is 'no longer required and can be removed.

As an alternative to extinguishment by detonation, the screen, water cooled if required, is inserted directly into the flame and lowered into a position in close proximity to the point of rupture so that the flame from leaves the rupture point and attaches itself to the screen. The screen is then slowly raised to a position above the rupture point, lifting the flame with it and permitting the workmen to repair the rupture.

wells, the economic losses are staggering and can amount to millions of dollars as a result of damage to wildlife, fisheries, property, beaches, and other aspects of the environment. Thus, particularly with offshore drilling, the rupture of anoil well whether ignited or not represents a very severe pollution problem.

With gas wells, the spewing of unburned gas presentsa serious danger of explosion to the surrounding area and to workmen who must cap the ruptured well while surrounded by noxious and highly flammable fumes.

SUMMARY OF THE INVENTION The present invention provides a device and method to control and prevent the dispersion of oil or gas'issuing from a ruptured well pipe. The invention involves the intentional ignition, if necessary, of the escaping oil or gas to cause it to burn in the atmosphere and thus prevent oil pollution or gas dispersion and to preclude the necessity for its removal. In order to accomplish such a condition and still provide necessary access for workmen to the ruptured area to carry out a capping operation, a unique apparatus is provided to lift the gas or oil flame from the open end of the ruptured pipe and to maintain the flame or confine the flame harmlessly in this position. With the flame thus lifted" above the ruptured pipe end, workmen are afforded the opportunity to proceed with capping and sealing of the ruptured pipe, unhampered by the flame.

In particulanthere is provided a,member in the form of a screen which is designed to pass fluid which is issuing under pressure from a ruptured oil and/or gas well pipe and which extracts heat with suflicient efficiency to substantially confine burning of the fluid to a region above the screen. The screen is formed with heat dissipating fins and coolant fluid conduits set BRIEF DESCRIPTION OF THE DRAWINGS FIG. 4 is a view taken on line 4-4 of FIG. 2 in the direction of the arrows;

FIG. 5 is a view taken on line 5-5 of FIG. 4 in the direction of the arrows; and

FIGS. 6a and b are cross-sectional views of alternative con duit portions of the apparatus.

DETAILED DESCRIPTION As required, detailed illustrative embodiments of the inven- ,tion are disclosed herein. However, it is to be understood that ,these embodiments merely exemplify the invention which may take many different forms that are radically different from the specific illustrative embodiments disclosed. Therefor, specific structural and functional details are not to be interpreted as limiting, but merely as a basis for the claims which define the scope of the invention.

Referring to FIG. I, there is illustrated an offshore drilling rig l0 erected in a body of water 12 and about a well pipe 14.

. The well pipe 14 extends downwardly into a subterranean reservoir 16 of oil and gas which by reason of the pressure of gases in the reservoir has blown the pipe 14 causing a rupture at 18 and spewing therefrom as indicated at 20. Although the particular reservoir. 16 is illustrated as containing oil, similar ruptures can occur with a reservoir of natural gas. As a result of the rupture, the oil is discharged in geyserlike fashion and ignites sending a large, high temperature flame 22 several hundred feet into the atmosphere. I

In the'drawing, the flame 22 is illustrated as limited or confined to a region above flame lifting apparatus 24 as will be described hereinafter in more detail. Briefly, the apparatus includes a heat dissipating member 26 and a thermal radiation shield 28 connected thereto and supported on adjustable mounting legs 30. A water pump 32 pumps water drawn through a conduit 34 from the body of water 12 and through inlet and outlet hoses 36 and 38 respectively to cool the member 26 to thereby aid in dissipating heat from the spewing mixture of gas and oil 20. The result is confinement of the flame 22 to a region on or slightly above the heat dissipating member 26.

Operation of the flame lifting apparatus 24 is based on fundamental requirements of combustion. For combustion to be self-sustaining, the fuel must be heated above its kindling temperature. In a typical flame of a hydrocarbon burning in air, heat is radiated in all directions from the flame, including the direction of the oncoming fuel. This radiation, plus some local convective heat transfer to the oncoming fuel serves first to vaporize the fuel (if it is a liquid) and then to raise the temperature of the combustible vapor to its ignition or kindling point. If heat is prevented from reaching the oncoming fuel, or alternatively, if heat is extracted from the fuel at the same or greater rate than as introduced by the flame, the fuel will be prevented from reaching its kindling temperature; combustion below this point of heat extraction is not possible. The flame lifting apparatus performs this function of extracting or dissipating heat from the flame with sufficient efiiciency so as to maintain the temperature of the fuel below its kindling temperature. This may beaccomplished by simply disposing a screen of heat conductive material in the path of fluid flow and additionally artificially cooling the screen if required. Whether such cooling would be required depends upon the volume of fluid passing through the screen, the particulars of construction of the screen and materials utilized, and the nature of the fluid. The more liquid the state of the fluid the less requirement there would be for artificial cooling inasmuch as the liquid fluid itself would serve to conduct heat from the outer surface of the column of fluid in conjunction with the screen.

Once operating, if the heat extracting screen is slowly raised a moderate amount, the flame inception zone will be raised a like amount since combustion will continue above the screen, but will not take place below the screen. The screen thus lifts the flame from the point of rupture of the well pipe. By appropriate design of the flame lifting apparatus 24, the flame can be raised or lifted percent to 30 percent of the free flame height. Thus, a free flame of 100 feet plume height can be raised 20 to 30 feet above its initial inception point and will continue to burn stably and reliably in this new position.

Referring to FIGS. 2 and 3, details of construction of one embodiment of flame lifting apparatus 24 are illustrated. Central to the apparatus is the heat dissipating member 26 in the form of a screen of heat conducting elements defining open spaced therebetween. The member 26 is defined perimetrically by four angle irons 40, 42, 44 and 46 each about 6 feet long, vertically about one foot wide and each having a horizontal outward projection, 47, 49, 51 or 53 of about 6 inches, and welded at their adjoining ends. A plurality of parallel sheet metal cooling fins 50 are disposed between one pair of opposite angle irons 40 and 44. Water inlet and outlet header tubes 52 and 54 respectively, are welded lengthwise to the other pair of posing angle irons 42 and 46. A plurality of holes are drilled through the angle irons 42and 46 and into the header tubes 52 and 54 aligned with holes fonned through the fins 50. A plurality of coolant tubes 56 are disposed through these openings so that vertical pairs of tubes 56 are aligned in parallel disposition. One method of construction of the screen member 26 is to feed fluid into one of the headers 52 at one endwhile closing the other end thereof and both ends of the header 54. Sufficient pressure is applied to expand the tubes 56 against the material of the fins 50 and header 1 tubes adjacent the openings for the'tubes 56 so as to tightly secure the tubes 56 in connection with the fins 50 and headers 52 and 54. The cooling fins 50 may be provided with lines of weakness, or notches, so as to be readily broken away by flying rocks and the like, carried by the fluid stream, without damage to the remainder of the screen.

An inlet manifold tube 58 is welded to one end of the inlet header 52 and the opposite end of the header 52 is closed. The open end of the inlet manifold 58 is screw threaded (not shown). Narrower, flexible connecting tubes 60 and 62 extend laterally from the manifold tube 58 for purposes hereinafter described. A flexible hose 64 is connected to the threaded end of the manifold tube 58 by means of a quick disconnect coupling 66. An outlet manifold tube 68 is similarly connected to one end of the outlet header tube 54, diagonally from the inlet manifold tube 58, and the opposite end of the outlet header tube 54 isclosed. The outlet manifold tube 68 is also formed with a pair of narrower, flexible lateral connecting tubes 70 and 72 for purposes hereinafter described. A flexible hose 74 is connected by a quick disconnect coupling 76 to the screw-threaded outlet end of the outlet manifold tube 68.

A circular radiation heat shield 28 is formed from four panels of lightweight, highly reflective sheet metal such as polished or gold plated aluminum, 78, 80, 82, 84, each segment having its inner edges 79, 81, 83, or cut to the length of the angle irons 40, 42, 44, 46. Four elongate aluminum tees 86, 88, and 92, are connected at their ends by means of bolts 94 and nuts 96 to the horizontal angle iron projections 47, 49, 51 and 53, at the comers of the screen member 26. The top flange portion of each tee 86, 88, 90 and 92 is inversely gabled. Referring additionally to FIG. 4, the aluminum panels 80 and 82 are shown with their side edges overlapping the angled side edges 98 and 100 of the tee 88 and secured thereto by a plurality of bolts 102 and nuts 104 as shown. By such means, the aluminum panels 78, 80, 82 and 84 are assembled around the perimeter of the screen member 26 to constitute a thermal radiation shield 28 having a diameter of about 20-40 feet. Pressure vent holes 55 are formed in the aluminum panels 78, 80, 82 and 84 so as to equalize vertical pressure differentials across the radiation shield 28 which are caused by the reduced density of the hot burning gases above the shield. However, it may well be desirable to limit the size and number of such holes whereby to promote the .flow of cooling air through-the screen as a result of the reduced density pressure gradient to the'point where water cooling may not be necessary.

Referring back to FIG. 2 in conjunction with FIGS. 4 and 5, curved coolant tubes 106, 108, 110, 11 2,are secured to the under side of the aluminum panels 78, 80, 82 and 84 respectively by means of plasma sprayed aluminum or copper, such as at 114 and are formed with threaded ends (not shown) whereby quick disconnect couplings 116 can be applied. By such means, the inlet manifold connecting tubes 60 and 62 are connected to the shield coolant tubes 106 and 108, the outlet manifold connecting tubes 70 and 72 are connected to the coolant tubes 110 and 112 and linking hose 118 is connected between the coolant tubes 108 and 110 and 112 and 106. As a result of these connections, when coolant water is fed into the inlet manifold tube 58 it travels through the coolant tubes 106,

108, 110, and 112 and outof the outlet manifold tube 68.

Simultaneously, water is conducted through the inlet header 52, screen coolant tubes 56, outlet header 54 and out through the outlet manifold tube 68.

Referring back to FIG. 3, the screen member 26 is supported on four adjustable mounting legs 30, one, in each corner. Each mounting leg 30 is secured to the screen member 26 by means of a ball joint 120 and connected by bolts 122 and nuts 124 at the top of the mounting leg 30, and welded at its upper end to the respective horizontal projection 47, 49, 51 or 53. Each mounting leg 30 includes an upper elongate member 126 which can be square tubing connected by a collar 128 to a lower, ratchet member 130. A climbing jack 132 is secured to the bottom of the upper member 126 and is positioned to climb along the ratchet surface 134 when its jack arm l36is manipulated. A reversing cam is provided (not .shown) for reversing the jack movement. A locking ball joint formed with a projecting angle member 140 fitted with one or more holed through which bolts such as 142 can be disposed for securing the locking joint to any convenient location. In this particular illustration, the mounting leg 30 is secured to the drilling platform but any convenient object can be used, such as pilings, rafts, etc. as available and appropriate for use.

An adjustable strut 144 is secured by pivot pins 146 and 148 between the upper mounting leg member 126 and corresponding aluminum tee, in this case tee 88. Each strut includes mutually slidable shafts 150 and 152 retained by a collar 154 secured to one end of the shafts 150 and by means of a bolt 156 and nut 158 through the end of the other shaft 152 and through one of a plurality (not shown) of openings along the length of the shaft 150.

In utilizing the equipment, various components can be preassembled while other components can be brought to the site and assembled at the location of the rupture. The screen member 26 is constructed as described above with headers 52 and 54 at inlet and outlet manifolds 58 and 68 attached. It is carried together with the four adjustable mounting legs 30, four adjustable struts 144, four aluminum tees 86, 88, 90 and 92, four reflector panels 78, 80, 82 and 84, two connecting hoses 118, inlet and outlet hoses 54 and 74 and the various hardware required for interconnecting the components; After the flame has been extinguished by detonation or any other prior art method, the screen member 26 is connected to its mounting legs 30 and the tees 88 are secured to the horizontal angle iron projections 47, 49, 51 and 53. The reflector. panels 78, 80, 82 and 84 are then mounted and secured onto the tees 86, 88, 90-and 92. The connecting hoses 118 are coupled to the appropriate coolant coils 108 and 110 and 112 and 106 and the manifold connecting tubes 60 and 62 and 70 and 72 are connected to the appropriate coolant tubes 106 and 108 and 110 and 112.

The inlet hose 64 is connected to the pump 32 which in turn has a line 34 which is dropped into the water 12. The pump is turned on whereby to cool the screen member 26 and shield 28. By means of the jacks 132, the screen member 26 and shield 28 are raised to a level which is predetermined as appropriate. The spewing oil and/or gas above the screen member 26 would then be reignited bymeans of an auxiliary flame or spark device (not shown), which can be operated remotely, causing the oil or gas to burn with its flame front resting on or slightly above the screen member'26. Fluid below the screen member 26 remains unignited permitting workmen to approach the rupture area and begin the capping v or sealing process. Once the capping process is completed, the apparatus is no longer required and can be removed.

ln alternative embodiments, the entire apparatus can be preassembled with one shield panel omitted and the apparatus moved into place with the screen member 26 over the spewing fluid. Removal of at least one panel is required since the spewing fluid would prevent the passing of the panel directly thereover. However, the screen member 26 with its relatively open structure can be readily-positioned vertically above the ruptured end of the pipe casing and after positioning, the omitted. panel can then be secured into place.

In another alternative embodiment, the screen member 26 and shield 28 can be utilized without mounting legs 30 by suspending the apparatus by cable or otherwise above the ruptured pipe. Cables can be carried by cranes brought to the vicinity on barges, or if on land, on trucks, and lowered onto the burning well. By then slowly lifting the apparatus from the well through the entire free flame height, the fire can be extinguished.

Referring now to FIGS. 6a and b, there are illustrated alternative configurations for coolant tubes to be utilized with the screen member 26. In the apparatus of FlGS. 1-5, the screen coolant tubes 56 are cylindrical. However, the pressure and viscosity of the fluid and ability to readily moor the apparatus may require that the oil flow pressure drop through the screen member 26 be reduced. Such reduction may be accomplished by utilizing screen coolant tubes having aerodynamic crosssectional configuration. Since the oil flow pressure drop through the screen member 26 results in greater pressure below the screen member 26 than above, the pressure differential across the affected area tends to raise the apparatus into the fluid stream. Counteracting this raising force, prior to mooring is the weight of the apparatus and the contained cooling water. By use of a coolant tube having an elliptical cross section, as illustrated in FIG. 6a, a reduction in oil flow pressure drop can be accomplished. 0n the other hand, if the mooring is satisfactory, it may be desired to reduce the amount of backsplash of oil and this can be accomplished by using coolant tubing 162 having an oval exterior cross section, as illustrated in FIG. 6b. The oval cross section is accomplished by welding an auxiliary triangular tube 163 onto a cylindrical tube 164, as illustrated. Other variations can be utilized for particular purposes.

I claim: 1. Pollution control apparatus for use on fluid comprising oil and/or natural gas which is issuing under pressure from an open wellpipe, and which is either intentionally ignited or allowed to burn to thereby prevent environmental pollution by unburned fluid, comprising: 1

a member formed to pass said fluid and conduct heat from said burning fluid whereby to substantially confine buming of said fluid to a region above said member; and

means for disposing'said member above and spaced from the open end of said well pipe during said confined burnmg.

2. The invention according to claim 1 including means for raising said member from a position above and adjacent said open pipe end to a position spaced vertically therefrom.

3. The invention according to claim 1 including mounting legs on said member and means on said mounting'legs for extension thereof whereby to raise said member from a position adjacent said open pipe end to a position spaced vertically therefrom.

4. The invention according to claim 1 including a thermal radiation shield and means for disposing said shield perimetrically of said member.

5. The invention according to claim 4 including means for applying coolant fluid to said shield.

6. The invention according to claim 4 in which said member and shield are formed with coolant fluid conduits and including a manifold connecting said conduits and means for applying coolant fluid to said manifold.

7. The invention according to claim 1 including means for circulating coolant fluid through said member.

8. The invention according to claim 1 in which said member is formed with a coolant fluid conduit and including a coolant fluid line, means for applying coolant to said line and a quick disconnect coupling between said line and said conduit.

9. The invention according to claim 1 in which said member comprises a screen of heat conducting'elements defining open spaces therebetween.

10. The invention according to claim 9 in which said heat conducting elements comprise elongate fins.

11. The invention according to claim 9 in which said heat conducting elements comprise elongate coolant tubes.

12. The invention according to claim 11 in which said tubes are formed avoid in exterior cross section and disposed with the wider side thereof downwardly.

13. The invention according to claim 1 including means for movement of sufficient air through said member for confinement of burning of said fluid above said member.

14. A method for controlling pollution from oil and/or natu ral gas which is issuing under pressure from an open well pipe and which is either intentionally ignited or allowed to burn to thereby prevent environmental pollution by unburned fluid, comprising disposing a heat conducting, fluid passing member in the path of said burning fluid and spacing said member from the open end of said well pipe whereby to permit said fluid to flow unconfined from said open end to said member and to confine burning of said fluid to a region above said member.

15. The invention according to claim 14 including the steps of disposing said member above and adjacent said open pipe end and raising said member above and adjacent said open pipe end and raising said member to a position spaced vertically therefrom.

16. The invention according to claim 14 including the steps of extinguishing said fire prior to disposing said member in said fluid path and then reigniting said fire above said member.

17. The invention according to claim 14 in which said member is initially disposed adjacent and above the open end of said well pipe and is then raised to said spaced position. 

2. The invention according to claim 1 including means for raising said member from a position above and adjacent said open pipe end to a position spaced vertically therefrom.
 3. The invention according to claim 1 including mounting lEgs on said member and means on said mounting legs for extension thereof whereby to raise said member from a position adjacent said open pipe end to a position spaced vertically therefrom.
 4. The invention according to claim 1 including a thermal radiation shield and means for disposing said shield perimetrically of said member.
 5. The invention according to claim 4 including means for applying coolant fluid to said shield.
 6. The invention according to claim 4 in which said member and shield are formed with coolant fluid conduits and including a manifold connecting said conduits and means for applying coolant fluid to said manifold.
 7. The invention according to claim 1 including means for circulating coolant fluid through said member.
 8. The invention according to claim 1 in which said member is formed with a coolant fluid conduit and including a coolant fluid line, means for applying coolant to said line and a quick disconnect coupling between said line and said conduit.
 9. The invention according to claim 1 in which said member comprises a screen of heat conducting elements defining open spaces therebetween.
 10. The invention according to claim 9 in which said heat conducting elements comprise elongate fins.
 11. The invention according to claim 9 in which said heat conducting elements comprise elongate coolant tubes.
 12. The invention according to claim 11 in which said tubes are formed avoid in exterior cross section and disposed with the wider side thereof downwardly.
 13. The invention according to claim 1 including means for movement of sufficient air through said member for confinement of burning of said fluid above said member.
 14. A method for controlling pollution from oil and/or natural gas which is issuing under pressure from an open well pipe and which is either intentionally ignited or allowed to burn to thereby prevent environmental pollution by unburned fluid, comprising disposing a heat conducting, fluid passing member in the path of said burning fluid and spacing said member from the open end of said well pipe whereby to permit said fluid to flow unconfined from said open end to said member and to confine burning of said fluid to a region above said member.
 15. The invention according to claim 14 including the steps of disposing said member above and adjacent said open pipe end and raising said member above and adjacent said open pipe end and raising said member to a position spaced vertically therefrom.
 16. The invention according to claim 14 including the steps of extinguishing said fire prior to disposing said member in said fluid path and then reigniting said fire above said member.
 17. The invention according to claim 14 in which said member is initially disposed adjacent and above the open end of said well pipe and is then raised to said spaced position.
 18. The invention according to claim 17 including the further step of raising said member until extinguishment of said fire.
 19. The invention according to claim 14 including the step of capping said well during burning of said fluid at said confined region.
 20. The invention according to claim 14 in which said well pipe protrudes from a body of water and including the step of applying water from said body of water to said member as coolant therefor. 